integration: Fix 'go test --tags cluster_proxy --timeout=30m -v ./integration/...'

grpc proxy opens additional 2 watching channels. The metric is shared
between etcd-server & grpc_proxy, so all assertions on number of open
watch channels need to take in consideration the additional "2"
channels.

integration/cluster_direct.go

@@ -23,6 +23,8 @@ import (
 	pb "go.etcd.io/etcd/etcdserver/etcdserverpb"
 )
 
+const throughProxy = false
+
 func toGRPC(c *clientv3.Client) grpcAPI {
 	return grpcAPI{
 		pb.NewClusterClient(c.ActiveConnection()),

integration/cluster_proxy.go

@@ -25,6 +25,8 @@ import (
 	"go.etcd.io/etcd/proxy/grpcproxy/adapter"
 )
 
+const throughProxy = true
+
 var (
 	pmu     sync.Mutex
 	proxies map[*clientv3.Client]grpcClientProxy = make(map[*clientv3.Client]grpcClientProxy)

integration/v3_watch_test.go

@@ -1241,7 +1241,15 @@ func TestV3WatchCancellation(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	if minWatches != "1" {
-		t.Fatalf("expected one watch, got %s", minWatches)
+	var expected string
+	if throughProxy {
+		// grpc proxy has additional 2 watches open
+		expected = "3"
+	} else {
+		expected = "1"
+	}
+
+	if minWatches != expected {
+		t.Fatalf("expected %s watch, got %s", expected, minWatches)
 	}
 }